The invention relates to a method for assembling the rubber dome into the keyboard and the structure of the keyboard associating with the method.
In general, the keyboard mainly includes, other than a plurality of key caps, a plurality of robber domes, an upper casing, a membrane circuit sheet and a lower casing. During the production of the upper casing, a plurality of housings are formed simultaneously. Each housing is used to receive a key cap and a rubber dome. The structure of each push button switch of keyboard includes a key cap, a rubber dome which turns on a corresponding membrane switch on the membrane circuit sheet then the key cap is depressed. As well known in the arts, the rubber dome is disposed into the housing from the side of the bottom surface of the upper casing. On the other hand, the key cap is disposed into the housing from the side of the top surface. The top surface of the keyboard is the surface facing the user. The bottom surface of the keyboard is the surface opposite to the top surface and faces the lower casing of the keyboard. The function of each component of the push button switch is well known in the arts.
Typically, there are two approaches implementing the rubber domes within the keyboard. One type is in form of an integral sheet with a multiple of rubber domes formed thereon and another type is in form of a single rubber dome isolated from other rubber domes within other housings. Integral sheet type rubber domes are formed by producing a plurality of (around 125) of rubber domes at the same time integrally. Each rubber dome is connected to each other by an integral rubber sheet during production. The advantage of the integral sheet type is its capability of disposing each of all rubber domes into their corresponding housings by single operation. However, when considering the operation purpose of the rubber dome itself, more than half of the rubber material of the integral sheet type rubber domes is for connection purpose and wasted. To save the material cost of the rubber within the keyboard, a single rubber dome configuration mentioned above is adopted.
In contrast, in the single rubber dome configuration, a plurality of the rubber domes are made simultaneously without connecting one rubber dome with other rubber domes. Therefore, no rubber material is wasted. However, as stated below, the assembly process of the rubber domes into the housings for the single rubber dome configuration involves more tedious procedures than the integral sheet type rubber domes.
To assembly the rubber domes for the single rubber dome configuration within their housings, the straight forward way is to insert one rubber dome into one housing of the upper casing one by one by the human effort. This approach obviously involves intensive human labors and is cost ineffective and time consuming.
Another way is first pouring a multiple of rubber domes over the bottom surface of upper casing. Afterwards, a human or a mechanical vibration action is input to dispose each rubber dome over the bottom surface of upper casing into one corresponding housing. At the end of the procedure, a number of rubber domes are leftover and no received in any one of the housings. If some housings do not have one rubber dome therein, the operator then feeds the rubber dome by hand into the empty housings. The leftover rubber domes located at positions other than housings are also picked up and removed by operator. The procedure spent on the removal of the leftover rubber domes is timing consuming and cost ineffective.
To the mentioned disadvantages, the present invention provides a method and a keyboard thereof which quickly removes the leftover rubber domes and therefore improves the assembly efficiency of the rubber domes.
The upper casing of the keyboard of the invention defines a bottom surface and a top surface and includes a multiple of housings distributed over a central portion of the bottom surface. Each housing receives one rubber dome. The method includes the steps of pouring a plurality of rubber domes over the bottom surface of the upper casing; shaking the upper casing in order to dispose one rubber dome into one corresponding housing while a number of rubber domes are leftover and not received in any one of the housings; engaging a membrane circuit sheet with the central portion of the bottom surface; flipping the upper casing over such that the leftover rubber domes not covered by the membrane circuit sheet are cleaned up.
The advantages and the details of the invention may be further understood by the following recitations and appended drawings.